Obesity wars: Molecular progress confronts an expanding epidemic

The worldwide prevalence of obesity is increasing at an alarming rate, with major adverse consequences for human health. This obesity epidemic is paralleled by a rapid and substantive increase in our understanding of molecular pathways and physiologic systems underlying the regulation of energy balance. While efforts to address the environmental factors that are responsible for the recent epidemic must continue, new molecular and physiologic insights into this system offer exciting possibilities for future development of successful therapies.